The purpose of this K01 Mentored Research Scientist Development Award is to support the applicant in developing the skills necessary to become an independent researcher in the implementation and sustainment of autism-related interventions in school settings. Autism spectrum disorder (ASD) is a complex and lifelong developmental disability that affects 1 in 88 children in the United States. With the growing number of children with ASD enrolled in public schools, it is imperative that schools implement and sustain evidence- based interventions (EBIs) to improve children's academic, behavioral, and social outcomes. The 2012 Interagency Autism Coordinating Committee Strategic Plan for ASD Research states that successful implementation in community settings of EBIs is lacking, and there are no specific studies that examine these issues. This K01 application capitalizes on an existing university-community partnership with the School District of Philadelphia to systematically examine implementation issues of a district-mandated autism EBI in urban public schools on a large scale. Under the mentorship of David Mandell, ScD, and a team of expert consultants, the proposed training and research activities will enable the applicant to: 1) understand which organizational factors affect implementation in schools; 2) develop expertise in mixed methods design to understand how organizational factors promote or impede implementation processes in public schools; and 3) acquire expertise in developing implementation interventions to address modifiable variables to improve the use and sustainment of autism EBIs in schools. The research activities associated with these training goals include three aims that build upon each other. Aim 1 will use quantitative methods to examine staff- and school-level factors as predictors of implementation and sustainment of an EBI for children with ASD. Aim 2 will use qualitative methods to further explore the staff-and school-level factors uncovered in Aim 1 by closely examining the implementation processes for a subset of high and low performing classrooms implementing an EBI for children with ASD. Lastly, in Aim 3, the applicant will develop an implementation intervention to support schools in their use and sustainment of autism EBIs. Findings from the proposed research projects have the potential to provide schools with the necessary supports to use EBIs and markedly improve the academic, behavioral, and social outcomes of children with ASD in public school settings.